"""Settings, and refusing the ones that cannot work."""

import pytest

from dora_joy.config import Config


def test_the_first_pad_is_the_default():
    assert Config.from_env().joystick_index == 0


def test_the_index_comes_from_the_environment(monkeypatch):
    monkeypatch.setenv("JOYSTICK_INDEX", "2")

    assert Config.from_env().joystick_index == 2


def test_an_index_that_is_not_a_number_names_the_variable(monkeypatch):
    monkeypatch.setenv("JOYSTICK_INDEX", "left")

    with pytest.raises(ValueError, match="JOYSTICK_INDEX"):
        Config.from_env()


def test_a_negative_index_is_refused_at_startup(monkeypatch):
    # Not at the first read of the pad, which is the one moment nobody is
    # watching the node's stderr.
    monkeypatch.setenv("JOYSTICK_INDEX", "-1")

    with pytest.raises(ValueError, match="JOYSTICK_INDEX"):
        Config.from_env()